1. Field of the Invention
This invention relates to a locking arrangement for a switchgear cabinet, having a lock and two locking bars, wherein the locking bars can be displaced in opposite directions with respect to each other when the lock is operated.
2. Description of Prior Art
Such a locking arrangement is known from German Patent Reference DE 195 36 906 C1. A lock housing, which is placed on a front of a cabinet door, is used in connection with this locking arrangement. A pinion is rotatably seated in the lock housing. Two pushrods can be driven and displaced in opposite directions to each other by the pinion. The pushrods have shoulders which extend through a door leaf. The locking bars are connected to the back of the door leaf. To enter into a locked state, the ends of the locking bars can be inserted into opposite locking elements, which are attached to the switchgear cabinet, as illustrated in German Patent Reference DE 90 10 175 U1.
Switchgear cabinet doors are customarily sealed against the switchgear cabinet, for which purpose sealing beads are used, which are applied as a foam on the insides of the switchgear cabinets. When closing the switchgear cabinet door, it is necessary to overcome the sealing pressure originating in the sealing bead.
It is one object of this invention to provide a locking arrangement of the type mentioned above, but wherein seal counterpressures created when the switchgear cabinet door is closed can be simply overcome.
This object is attained because in end areas facing away from the lock, the locking bars are hingedly coupled to respective lever arms of a locking lever. The locking lever has a second lever arm which is coupled to the first lever arm in the area of a pivot hinge and which has an inclined pad. The pivot axis of the pivot hinge is arranged at a distance with respect to a direction of push of the associated locking bar.
The locking forces generated by the lock can be reduced by the pivot lever. The lever forces generated are used for locking, wherein it is also possible to overcome high sealing forces, in particular.
In accordance with one preferred embodiment of this invention the lock has a pinion which meshes with teeth in the locking bars. The locking bars are arranged on diametrically opposite sides of the pinion, and the hinge axes of the hinges, which connect the locking bars with the first lever arm of the locking lever and the axis of rotation of the pinion, are located along one line. A symmetrical structure is thus created which can be used, for one, for simplifying the assembly. This locking arrangement can also be selectively used with doors which are hinged on the left or the right.
In accordance with one embodiment of this invention, the locking bars have a driving element and a connecting part, which are hingedly connected with each other. The driving element is maintained in a lock housing of the lock, and projects from the lock housing with a shoulder on which the connecting part is fastened. The locking lever is coupled to the end of the connecting part.
A simple construction of the locking bar results if it is made of a flat rod blank, from which the teeth are cut out on the lock side, and having a broad side in an area of the lock which extends vertically with respect to the plane of the connected door. Adjoining the lock, the flat bar blank is rotated by 90xc2x0 to form a connecting part and its broad side is arranged parallel with the plane of the door. The hinge axes of the hinges connecting the locking lever with the locking bars extend vertically with respect to a plane of the door.
In the area of the ends facing the hinges the locking bars are flattened, and the first lever arm of the pivot lever is maintained in the area between the door leaf and the flat place. This results in a space-saving arrangement.
The pivot axis of the locking lever preferably extends vertically with respect to the plane of the door.
The locking lever can be designed as a one-piece stamped and bent element for reasons of simplifying its production.
To prevent the pivot hinge from highly mechanically stressing during the locking process, because of the sealing pressure created, on a side located opposite the inclined pad on the other side of the pivot hinge, the locking lever has a support element which is braced on an inside of the door.
In this case the support element can advantageously be designed as a stamped-out part projecting in a direction toward the door.
One embodiment of a locking device in accordance with this invention can be distinguished because the locking bars and the lock are attached to a locking cabinet door of a double door of a switchgear cabinet. The lock can be operated from the front of the locking cabinet door, and the front of the lock is covered by a closed cabinet counter door. Thus the lock is no longer accessible when the double doors of the switchgear cabinet are closed.